【正确答案】正确答案：Systemic functional grammar, developed by M. A. K. Halliday, is a socially oriented functional linguistic approach and one of the most influential linguistic theories in the twentieth century. Systemic functional grammar is based on two facts; Language users are actually making choices in a set of systems and trying to realize different semantic functions in social interaction. Language is inseparable from social activities of man. Thus, it takes actual uses of language as the object of study. One point to notice is that it takes clause as the basic unit. It consist of two inseparable parts: systemic grammar and functional grammar.